For equipment on high voltage platforms along high voltage transmission lines, a problem is to assure an auxiliary power supply even when the power lines are without power. Today laser light is transmitted from the ground through fibre optics up to the platform, but with this method it is not possible to transmit more than approximately 0.5 W per optical fibre. The equipment must be able to operate even when the power lines are without power, such as during service or when a fault has occurred along the power lines, to protect equipment from damage caused by stroke of lightning. Existing systems for supplying energy are not able to meet these demands.
DE 1807 591 discloses a high voltage breaker arranged on a platform. The breaker is provided with an actuator powered by an effectuating capacitor. The effectuating capacitor is charged by an energy converter, converting chemical or mechanical energy into electric energy. As an example the energy converter can be a fuel cell.
A problem with a supply device of this kind is that a conventional capacitor of this kind leaks energy such that it repeatedly has to be recharged. Furthermore when the capacitor has been in use it has to be recharged. The power from a fuel cell is normally to low to allow recharging within reasonable time. Alternatively a particular powerful and costly fuel cell has to be used.